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Today's applications are powered by data, just like machines are powered by energy. In this series of blogs, we will look at how applications use data, how data is organized and what effect it has on the evolution of functionality. A professionally managed product will typically have this context: The product itself: X-ray equipment, Surgery devices, Ultrasound machines, toothbrushes and so on. A sales person would be in the process of getting a customer interested A customer would need consumables - like a new brush Many of these equipment produce images A customer would own one or more equipment A service engineer would service a set of equipment A product will have parts that are replaceable Spares would be stocked In today's world, each of these aspects are supported through applications. Application experience is enhanced with data. How do we store and correlate the data, so that it's usable? One way is to structure the data by modeling using Entit

A Relational Database models data in the form of tables and relation between tables. Consider the following application: When a customer asks a question about an equipment, we want to connect to an expert who can answer. For example, an expert on Ultrasound is different from an expert on X-ray; and there are different experts in different countries. One way to model this data is to make a table with the equipment identifier and the contact of the expert. As you can see, there's a lot of redundancy; the expert's contact is replicated in multiple rows. Not only is this inefficient in terms of storage, but also multiple updates need to be done when there's a new expert. How could we solve this? Any identification we repeat will have the same redundancy. The answer is to remove redundancy - normalize the data. The best normalizations are the ones that reflect the real world. In this case, the equipment and the region are linked to the contact. So one way to organize th

SQL is a language used to transact with a Relational Database. If you are unfamiliar with SQL, you can quickly get a flavor for it over here:  https://www.w3schools.com/sql/ SQL statements can be used to create, delete and update databases. The concept is based on the principle of transactions - till you commit a set of modifications, none of them are done. When you commit, all of them are done together. This way, 'integrity' of the data is guaranteed. However, strict schema management may have its downfalls... What if we need to add columns or the type of a column changes? What happens to applications that were written with old assumptions in mind? In the example we saw before, what if the schema changes? Let's say we discover that the economic zone is more important than the region. So we'd like to replace the region field. Economic zones have abbreviations like ASEAN, EMEA, etc. This change may be driven by considerations of cost: Costs are less when the pa

Welcome to this series of blogs. Let's do a review of our favorite languages! Looking for the next piece on Applications ^ Data? See here! These blogs are designed to trigger questions and discussions. It's not about being right or wrong. The purpose is to discover, know and develop. Feel free to leave comments, ask and answer questions, voice opinions and enjoy! Guideline : Please be respectful and welcoming of everyone's views and questions. You are now a part of our team :) Click here  to attempt the  assessment of this series Notes: - You can login using your gmail id . If you have provided us the gmail id already, it will succeed. - Otherwise, please write a mail from your gmail id to sudeep@rapalearning.com with subject Bootcamp access - Each lesson has an assessment. Each assessment can be submitted once. Here's is a sequence we suggest: Building block of polymorphism : Start here for a fun exercise to program an artillery firing sequence... in C

Functions are famously called first-class citizens of the JavaScript world. Functions can smoothly be treated as a variable,  For example, if we execute this in a browser: function myFunction(a, b) {   return a * b; } var x = myFunction; console.log(x(3,4)); It will log 12. The declaration of myFunction makes it a 'value', which is assigned to a variable 'x'. Notice that there are no parenthesis in that assignment. Next, we have a log that invokes myFunction by applying the parenthesis () operator on the variable. The log statement logs the return value of myFunction, which is the product of 3 and 4. Let's say we forget the parenthesis: console.log(x); This will log the function itself! Try it out in your browser by enabling the console display via the 'developer tools' option. Of course, this will just call the function normally: var x = myFunction(3,4); It's just the application of the () operator to call a

JavaScript is a versatile language that's used in programming everything from web pages to servers and desktop applications. We will use this interactive tutorial  as a reference in our journey. JavaScript is different from the other languages we've seen here (C++, C#, Java), in that it doesn't have a compiler. The code is interpreted while running it. This brings us to a distinction in data-types as well. JavaScript doesn't fix the type of its variables. For example, this is a valid sequence for the interpreter: var x;           // x is undefined to start with x = 15;          // After this assignment, x is a Number x = "Phil";      // Here x becomes a String Many other fun things can happen with JavaScript data, as you can see here . What could be the use of such flexibility? Tell us what you feel below. Hint: Think of real-life arrays - like array of vehicles, array of chat messages, etc. Once you are done, let's step int